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Enzymes are proteins which act as a Biological Catalyst. A catalyst alters the rate of reaction without itself changes.

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Background Knowledge: Enzyme: Enzymes are proteins which act as a Biological Catalyst. A catalyst alters the rate of reaction without itself changes. Research indicates that enzymes combine with the molecules they act upon (called Substrates) to form an enzyme-substrate complex. The reaction that take place results in products from the original molecule, but leaves the enzyme unchanged. Enzyme controlled reactions can be either: 1. Anabolic - Building up larger molecules. 2. Catabolic - breaking down large molecule into smaller molecules Enzyme Reaction: Enzymes are protein molecules which are usually longer than the substrate. This means that only a small part of the enzyme, called active site, comes into contact with the substrate. ...read more.


At higher temperature, the enzyme's protein is denatured (changed). This results in the active sites changing shape and gradually declining in activity. 3. pH - Enzymes usually work efficiently within a narrow pH range. The graph shows that the enzyme works best within a pH range between 6.5 and 7.5. In greater acidity or alkalinity, the enzyme will be denatured. 4. Concentration -- As long as both temperature and pH are at optimum values and there is a high level of substrate, the rate of reaction will decrease as the enzyme concentration increase. 5. Substrate concentration - If the concentration of the enzyme remains the same vthan a maximum rate of reaction will not be exceeded however much the substrate concentration is increased. ...read more.


If they are moving quicker, they are going to have more collisions. (In order to do this-Heat up Hydrogen peroxide). 2. Concentration (or pressure) - If the solution is made more concentrated it means there are more particles of reactant knocking about between the water molecules which makes collisions between the important particles more likely. 3. Size of solid particles (or surface area) - If one of the reactant is a solid then breaking it up or cut it into smaller pieces will increase its surface area. This means the particles around it in the solution will have more area to work on so there will be more collisions that are useful. 4. Catalyst - A catalyst works by giving the reacting particles a surface to stick to where they can bump into each other. This obviously increases the number of collision too. ...read more.

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